Displaying publications 1 - 20 of 151 in total

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  1. Fulltext ZnCl2 catalyzed new coumarinyl-chalcones as cytotoxic agents
    Sathish Kumar K, Kotra V, Phani Kumar Kola, Praveena Devi CB, Anusha N, Hari Babu B, et al.
    Saudi J Biol Sci, 2021 Jan;28(1):386-394.
    PMID: 33424321 DOI: 10.1016/j.sjbs.2020.10.020
    A new series of coumarin-yl-chalcone derivatives (3a-m) had been designed and synthesized through different reactions such as aromatic addition, cyclization and Claisen-Schmidt reactions in good yields (54-78%). 5-acetyl-4-(2-hydroxyphenyl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (1) has been synthesized by multi-component one pot reaction of salicylaldehyde, methyl acetoacetate and urea, which was further reacted with malonic acid employing ZnCl2 catalyst to yield 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (2). The title compounds (3a-m) were synthesised by reacting 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H)-one (2) with different aromatic aldehydes in the presence of potassium hydroxide. In silico studies, a preliminary screening method for predicting the anti-cancer activity was performed for the synthesized compounds (3a-m) against Src, Alb tyrosine kinase and homology model protein (PDB ID: 4csv). The derivatives 3h and 3m showed moderate binding energies. The in vitro cytotoxic activity was evaluated for the compounds 3h and 3m by using human cancer cell-line morphology and MTT assay against three human cell-lines A549 (Lung), Jurkat (Leukemia) and MCF-7 (Breast). The results indicate that the derivatives 3h and 3m display significant anti-cancer activity, however it was found to be less cytotoxic when compared to the standard used i.e. Imatinib.
  2. Visible-Light Driven Effective Photocatalytic Degradation of Methylene Blue Dye Using Perforated Curly Zn0.1Ni0.9O Nanosheets
    Karthikeyan V, Gnanamoorthy G, Varun Prasath P, Narayanan V, Sagadevan S, Umar A, et al.
    J Nanosci Nanotechnol, 2020 Sep 01;20(9):5759-5764.
    PMID: 32331175 DOI: 10.1166/jnn.2020.17898
    Herein, we report the facile synthesis, characterization and visible-light-driven photocatalytic degradation of perforated curly Zn0.1Ni0.9O nanosheets synthesized by hydrothermal process. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies confirmed the cubic phase crystalline structure and growth of high density perforated curly Zn0.1Ni0.9O nanosheets, respectively. As a photocatalyst, using methylene blue (MB) as model pollutant, the synthesized nanosheets demonstrated a high degradation efficiency of ~76% in 60 min under visible light irradiation. The observed results suggest that the synthesized Zn0.1Ni0.9O nanosheets are attractive photocatalysts for the degradation of toxic organic waste in the water under visible light.
  3. Fulltext Utilization of CRISPR-Mediated Tools for Studying Functional Genomics in Hematological Malignancies: An Overview on the Current Perspectives, Challenges, and Clinical Implications
    Solayappan M, Azlan A, Khor KZ, Yik MY, Khan M, Yusoff NM, et al.
    Front Genet, 2021;12:767298.
    PMID: 35154242 DOI: 10.3389/fgene.2021.767298
    Hematological malignancies (HM) are a group of neoplastic diseases that are usually heterogenous in nature due to the complex underlying genetic aberrations in which collaborating mutations enable cells to evade checkpoints that normally safeguard it against DNA damage and other disruptions of healthy cell growth. Research regarding chromosomal structural rearrangements and alterations, gene mutations, and functionality are currently being carried out to understand the genomics of these abnormalities. It is also becoming more evident that cross talk between the functional changes in transcription and proteins gives the characteristics of the disease although specific mutations may induce unique phenotypes. Functional genomics is vital in this aspect as it measures the complete genetic change in cancerous cells and seeks to integrate the dynamic changes in these networks to elucidate various cancer phenotypes. The advent of CRISPR technology has indeed provided a superfluity of benefits to mankind, as this versatile technology enables DNA editing in the genome. The CRISPR-Cas9 system is a precise genome editing tool, and it has revolutionized methodologies in the field of hematology. Currently, there are various CRISPR systems that are used to perform robust site-specific gene editing to study HM. Furthermore, experimental approaches that are based on CRISPR technology have created promising tools for developing effective hematological therapeutics. Therefore, this review will focus on diverse applications of CRISPR-based gene-editing tools in HM and its potential future trajectory. Collectively, this review will demonstrate the key roles of different CRISPR systems that are being used in HM, and the literature will be a representation of a critical step toward further understanding the biology of HM and the development of potential therapeutic approaches.
  4. Fulltext Trigeminal neuralgia, glossopharyngeal neuralgia, and myofascial pain dysfunction syndrome: an update
    Khan M, Nishi SE, Hassan SN, Islam MA, Gan SH
    Pain Res Manag, 2017;2017:7438326.
    PMID: 28827979 DOI: 10.1155/2017/7438326
    Neuropathic pain is a common phenomenon that affects millions of people worldwide. Maxillofacial structures consist of various tissues that receive frequent stimulation during food digestion. The unique functions (masticatory process and facial expression) of the maxillofacial structure require the exquisite organization of both the peripheral and central nervous systems. Neuralgia is painful paroxysmal disorder of the head-neck region characterized by some commonly shared features such as the unilateral pain, transience and recurrence of attacks, and superficial and shock-like pain at a trigger point. These types of pain can be experienced after nerve injury or as a part of diseases that affect peripheral and central nerve function, or they can be psychological. Since the trigeminal and glossopharyngeal nerves innervate the oral structure, trigeminal and glossopharyngeal neuralgia are the most common syndromes following myofascial pain dysfunction syndrome. Nevertheless, misdiagnoses are common. The aim of this review is to discuss the currently available diagnostic procedures and treatment options for trigeminal neuralgia, glossopharyngeal neuralgia, and myofascial pain dysfunction syndrome.
  5. Fulltext Towards dynamic remote data auditing in computational clouds
    Sookhak M, Akhunzada A, Gani A, Khurram Khan M, Anuar NB
    ScientificWorldJournal, 2014;2014:269357.
    PMID: 25121114 DOI: 10.1155/2014/269357
    Cloud computing is a significant shift of computational paradigm where computing as a utility and storing data remotely have a great potential. Enterprise and businesses are now more interested in outsourcing their data to the cloud to lessen the burden of local data storage and maintenance. However, the outsourced data and the computation outcomes are not continuously trustworthy due to the lack of control and physical possession of the data owners. To better streamline this issue, researchers have now focused on designing remote data auditing (RDA) techniques. The majority of these techniques, however, are only applicable for static archive data and are not subject to audit the dynamically updated outsourced data. We propose an effectual RDA technique based on algebraic signature properties for cloud storage system and also present a new data structure capable of efficiently supporting dynamic data operations like append, insert, modify, and delete. Moreover, this data structure empowers our method to be applicable for large-scale data with minimum computation cost. The comparative analysis with the state-of-the-art RDA schemes shows that the proposed scheme is secure and highly efficient in terms of the computation and communication overhead on the auditor and server.
  6. Tobacco consumption and illegal drug use among Bangladeshi males: association and determinants
    Kabir MA, Goh KL, Khan MM
    Am J Mens Health, 2013 Mar;7(2):128-37.
    PMID: 23065136 DOI: 10.1177/1557988312462737
    This article aimed to identify the determinants of tobacco consumption and illegal drug use (IDU) as well as to examine the association between these two variables using a representative sample of 3,771 Bangladeshi males aged 15 to 54 years. Data were collected through Bangladesh Demographic and Health Survey 2007. To identify the determinants, the patterns of tobacco consumption and IDU were analyzed by age, education and occupation, residence, mass media, premarital sex, wealth, and sexually transmitted infections (STIs). Prevalence of smoking cigarette and bidi was roughly 60%. However, the prevalence of IDU was 3.4%, and this proportion is statistically significant (Z = 11.32, p = .000). After bivariate analysis, almost all variables except STIs were significantly associated with tobacco consumption. Similarly, all variables except residence and mass media were associated with IDU. Based on multivariable adjusted logistic regression analysis, the likelihood of using IDU was approximately twofold (odds ratio [OR] = 1.8, 95% confidence interval [CI] = 1.23-2.53) among bidi smokers and fourfold (OR = 3.8, 95% CI = 2.62-5.56) among cigarette smokers as compared with nonsmokers.
  7. Fulltext Tick fauna of Malaysian red jungle fowl (Gallus gallus) in Bangi, Malaysia
    Konto M, Fufa GI, Zakaria A, Tukur SM, Watanabe M, Ola-Fadunsin SD, et al.
    Vet World, 2015 Oct;8(10):1167-71.
    PMID: 27047012 DOI: 10.14202/vetworld.2015.1167-1171
    The red jungle fowl is generally considered as one of the endangered Asian wild Galleopheasants due to man-made encroachment of their habitats, coupled with the effect of disease and disease causing organisms like ticks and tick-borne infections. This study aimed to determine the tick fauna of the red jungle fowl and their predilection sites based on developmental stages.
  8. Fulltext The need for redesigned pharmacy practice courses in Pakistan: the perspectives of senior pharmacy students
    Umair Khan M, Ahmad A, Hussain K, Salam A, Hasnain ZU, Patel I
    J Educ Eval Health Prof, 2015;12:27.
    PMID: 26072905 DOI: 10.3352/jeehp.2015.12.27
    In Pakistan, courses in pharmacy practice, which are an essential component of the PharmD curriculum, were launched with the aim of strengthening pharmacy practice overall and enabling pharmacy students to cope with the challenges involved in meeting real-world healthcare needs. Since very little research has assessed the efficacy of such courses, we aimed to evaluate students' perceptions of pharmacy practice courses and their opinions about whether their current knowledge of the topics covered in pharmacy practice courses is adequate for future practice.
  9. The health burden of malaria and household choices regarding treatment and prevention in Pakistan
    Khan M, Mahmood HZ, Noureen S, Muhmood K, Husnain MIU, Hameed Khaliq I
    Trop Biomed, 2019 Sep 01;36(3):664-676.
    PMID: 33597488
    The extent of the economic burden of malaria and its imposed mechanisms are both relevant to public policy. This paper investigates the economic burden of malaria and household behaviour in relation to the treatment and prevention of the illness in Pakistan. In this regard, data were collected from a randomly selected sample of 360 households using structured questionnaires. The survey results indicate that 23.4% of household members contracted malaria during the three-month reference period. The average per person cost of malaria is estimated at 3116 Pakistani rupees (PKR) (USD 32). The estimated cost of the illness was found to be equivalent to, on average, 6.7% of monthly household income. Although high-income households face a higher financial burden due to better preventive and mitigation measures, the negative consequences hit low-income households harder due to liquidity constraints and poor access to effective treatment. We recommend that malaria control policies be integrated into development and poverty reduction programs.
  10. The effect of losartan and carvedilol on vasopressor responses to adrenergic agonists and angiotensin II in the systemic circulation of Sprague Dawley rats
    Abdulla MH, Sattar MA, Abdullah NA, Khan MA, Anand Swarup KR, Johns EJ
    Auton Autacoid Pharmacol, 2011 Jan-Apr;31(1-2):13-20.
    PMID: 21166975 DOI: 10.1111/j.1474-8673.2010.00461.x
    1 Interaction between renin-angiotensin (RAS) and sympathetic nervous systems (SNS) was investigated by examining the effect of cumulative blockade of angiotensin II (Ang II) and adrenergic receptors in normal Sprague Dawley rats. 2 Rats were treated with losartan (10 mg/kg), carvedilol (5 mg/kg), or losartan plus carvedilol (10+5 mg/kg) orally for 7 days. On day 8, the animals were anaesthetized with pentobarbitone and prepared for systemic haemodynamic study. Dose-response relationships for the elevation of mean arterial pressure or change in heart rate (HR) in response to intravenous injections of noradrenaline (NA), phenylephrine (PE), methoxamine (ME) and Ang II were determined. 3 Losartan or the combination of losartan with carvedilol blunted vasopressor responses to ME and Ang II. Dose-response relationships for agonist action on HR were significantly inhibited by all treatments except for the combination of losartan and carvedilol on the decrease in HR induced by PE. Carvedilol decreased vasopressor responses to NA, PE and Ang II, and HR responses to NA, ME and Ang II. Combination treatment produced similar effects to losartan on the vasopressor and HR responses but had a greater effect on vasopressor responses to ME and Ang II, and on HR responses to NA and Ang II than carvedilol alone. 4 It is concluded that peripheral vasoconstriction induced by Ang II is partly mediated by adrenergic action and that the vasopressor responses to adrenergic agonists depend on an intact RAS. These observations suggest an interactive relationship between RAS and SNS in determining systemic haemodynamic responses in 'normal' rats.
  11. Fulltext The Current Situation Regarding Long-Acting Insulin Analogues Including Biosimilars Among African, Asian, European, and South American Countries; Findings and Implications for the Future
    Godman B, Haque M, Leong T, Allocati E, Kumar S, Islam S, et al.
    Front Public Health, 2021;9:671961.
    PMID: 34249838 DOI: 10.3389/fpubh.2021.671961
    Background: Diabetes mellitus rates continue to rise, which coupled with increasing costs of associated complications has appreciably increased global expenditure in recent years. The risk of complications are enhanced by poor glycaemic control including hypoglycaemia. Long-acting insulin analogues were developed to reduce hypoglycaemia and improve adherence. Their considerably higher costs though have impacted their funding and use. Biosimilars can help reduce medicine costs. However, their introduction has been affected by a number of factors. These include the originator company dropping its price as well as promoting patented higher strength 300 IU/ml insulin glargine. There can also be concerns with different devices between the manufacturers. Objective: To assess current utilisation rates for insulins, especially long-acting insulin analogues, and the rationale for patterns seen, across multiple countries to inform strategies to enhance future utilisation of long-acting insulin analogue biosimilars to benefit all key stakeholders. Our approach: Multiple approaches including assessing the utilisation, expenditure and prices of insulins, including biosimilar insulin glargine, across multiple continents and countries. Results: There was considerable variation in the use of long-acting insulin analogues as a percentage of all insulins prescribed and dispensed across countries and continents. This ranged from limited use of long-acting insulin analogues among African countries compared to routine funding and use across Europe in view of their perceived benefits. Increasing use was also seen among Asian countries including Bangladesh and India for similar reasons. However, concerns with costs and value limited their use across Africa, Brazil and Pakistan. There was though limited use of biosimilar insulin glargine 100 IU/ml compared with other recent biosimilars especially among European countries and Korea. This was principally driven by small price differences in reality between the originator and biosimilars coupled with increasing use of the patented 300 IU/ml formulation. A number of activities were identified to enhance future biosimilar use. These included only reimbursing biosimilar long-acting insulin analogues, introducing prescribing targets and increasing competition among manufacturers including stimulating local production. Conclusions: There are concerns with the availability and use of insulin glargine biosimilars despite lower costs. This can be addressed by multiple activities.
  12. Telluride-Based Materials: A Promising Route for High Performance Supercapacitors
    Khan AJ, Sajjad M, Khan S, Khan M, Mateen A, Shah SS, et al.
    Chem Rec, 2024 Jan;24(1):e202300302.
    PMID: 38010947 DOI: 10.1002/tcr.202300302
    As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined.
  13. Fulltext Teledentistry as a Supportive Tool for Dentists in Pakistan
    Subhan R, Ismail WA, Musharraf S, Khan M, Hafeez R, Alam MK
    Biomed Res Int, 2021;2021:8757859.
    PMID: 34540998 DOI: 10.1155/2021/8757859
    The current scenario of the COVID-19 pandemic has forced dentists to seek different options for delivering healthcare services other than the in-person direct examination in clinical practice. Teledentistry is one of the options for remote patient care and monitoring. Objective. The present survey was conducted to assess the knowledge and perception of the dentists in Pakistan regarding teledentistry as an emergent supportive tool. Materials and Methods. A self-administered, close-ended, and prevalidated survey questionnaire was used, comprising 21 questions, and distributed electronically via e-mail, WhatsApp, and Facebook Messenger to evaluate the knowledge and perception of dentists regarding teledentistry. The data collected was compiled in a systematic manner and analyzed in terms of frequency (yes/no). Results. Out of a total of 350 dentists, 325 responded to the questionnaire, and it was seen that 62.5% of them did not have knowledge about teledentistry prior to COVID-19. 65.8% of dentists considered the practice of teledentistry in nonpandemic situations in the future. Conclusion. In the present study, it was observed that most of the dental professionals had inadequate knowledge about teledentistry before COVID-19, but the awareness and perception regarding teledentistry were currently satisfactory among the dental professionals in Pakistan. This emerging trend gives a positive hope for the implementation of teledentistry in the healthcare setup of Pakistan in the near future, as it will prove to be beneficial for safe dental practice during times of pandemic and even after.
  14. Synthesis of enriched boron nitride nanocrystals: A potential element for biomedical applications
    Ahmad P, Khandaker MU, Muhammad N, Rehman F, Ullah Z, Khan G, et al.
    Appl Radiat Isot, 2020 Dec;166:109404.
    PMID: 32956924 DOI: 10.1016/j.apradiso.2020.109404
    The shortcomings in Boron neutron capture therapy (BNCT) and Hyperthermia for killing the tumor cell desired for the synthesis of a new kind of material suitable to be first used in BNCT and later on enable the conditions for Hyperthermia to destroy the tumor cell. The desire led to the synthesis of large band gap semiconductor nano-size Boron-10 enriched crystals of hexagonal boron nitride (10BNNCs). The contents of 10BNNCs are analyzed with the help of x-ray photoelectron spectroscopy (XPS) and counter checked with Raman and XRD. The 10B-contents in 10BNNCs produce 7Li and 4He nuclei. A Part of the 7Li and 4He particles released in the cell is allowed to kill the tumor (via BNCT) whereas the rest produce electron-hole pairs in the semiconductor layer of 10BNNCs suggested to work in Hyperthermia with an externally applied field.
  15. Synthesis and structure-activity relationship of thiobarbituric acid derivatives as potent inhibitors of urease
    Khan KM, Rahim F, Khan A, Shabeer M, Hussain S, Rehman W, et al.
    Bioorg Med Chem, 2014 Aug 1;22(15):4119-23.
    PMID: 24986232 DOI: 10.1016/j.bmc.2014.05.057
    A series of thiobarbituric acid derivatives 1-27 were synthesized and evaluated for their urease inhibitory potential. Exciting results were obtained from the screening of these compounds 1-27. Compounds 5, 7, 8, 11, 16, 17, 22, 23 and 24 showed excellent urease inhibition with IC50 values 18.1 ± 0.52, 16.0 ± 0.45, 16.0 ± 0.22, 14.3 ± 0.27, 6.7 ± 0.27, 10.6 ± 0.17, 19.2 ± 0.29, 18.2 ± 0.76 and 1.61 ± 0.18 μM, respectively, much better than the standard urease inhibitor thiourea (IC₅₀=21 ± 0.11 μM). Compound 3, 4, 10, and 26 exhibited comparable activities to the standard with IC₅₀ values 21.4 ± 1.04 and 21.5 ± 0.61 μM, 22.8 ± 0.32, 25.2 ± 0.63, respectively. However the remaining compounds also showed prominent inhibitory potential The structure-activity relationship was established for these compounds. This study identified a novel class of urease inhibitors. The structures of all compounds were confirmed through spectroscopic techniques such as EI-MS and (1)H NMR.
  16. Synthesis and molecular docking studies of potent α-glucosidase inhibitors based on biscoumarin skeleton
    Khan KM, Rahim F, Wadood A, Kosar N, Taha M, Lalani S, et al.
    Eur J Med Chem, 2014 Jun 23;81:245-52.
    PMID: 24844449 DOI: 10.1016/j.ejmech.2014.05.010
    In our effort directed toward the discovery of new anti-diabetic agent for the treatment of diabetes, a library of biscoumarin derivative 1-18 was synthesized and evaluated for α-glucosidase inhibitory potential. All eighteen (18) compounds displayed assorted α-glucosidase activity with IC50 values 16.5-385.9 μM, if compared with the standard acarbose (IC50 = 906 ± 6.387 μM). In addition, molecular docking studies were carried out to explore the binding interactions of biscoumarin derivatives with the enzyme. This study has identified a new class of potent α-glucosidase inhibitors.
  17. Fulltext Sustainability of rainwater harvesting system in terms of water quality
    Rahman S, Khan MT, Akib S, Din NB, Biswas SK, Shirazi SM
    ScientificWorldJournal, 2014;2014:721357.
    PMID: 24701186 DOI: 10.1155/2014/721357
    Water is considered an everlasting free source that can be acquired naturally. Demand for processed supply water is growing higher due to an increasing population. Sustainable use of water could maintain a balance between its demand and supply. Rainwater harvesting (RWH) is the most traditional and sustainable method, which could be easily used for potable and nonpotable purposes both in residential and commercial buildings. This could reduce the pressure on processed supply water which enhances the green living. This paper ensures the sustainability of this system through assessing several water-quality parameters of collected rainwater with respect to allowable limits. A number of parameters were included in the analysis: pH, fecal coliform, total coliform, total dissolved solids, turbidity, NH3-N, lead, BOD5, and so forth. The study reveals that the overall quality of water is quite satisfactory as per Bangladesh standards. RWH system offers sufficient amount of water and energy savings through lower consumption. Moreover, considering the cost for installation and maintenance expenses, the system is effective and economical.
  18. Fulltext Suicide numbers during the first 9-15 months of the COVID-19 pandemic compared with pre-existing trends: An interrupted time series analysis in 33 countries
    Pirkis J, Gunnell D, Shin S, Del Pozo-Banos M, Arya V, Aguilar PA, et al.
    EClinicalMedicine, 2022 Sep;51:101573.
    PMID: 35935344 DOI: 10.1016/j.eclinm.2022.101573
    BACKGROUND: Predicted increases in suicide were not generally observed in the early months of the COVID-19 pandemic. However, the picture may be changing and patterns might vary across demographic groups. We aimed to provide a timely, granular picture of the pandemic's impact on suicides globally.

    METHODS: We identified suicide data from official public-sector sources for countries/areas-within-countries, searching websites and academic literature and contacting data custodians and authors as necessary. We sent our first data request on 22nd June 2021 and stopped collecting data on 31st October 2021. We used interrupted time series (ITS) analyses to model the association between the pandemic's emergence and total suicides and suicides by sex-, age- and sex-by-age in each country/area-within-country. We compared the observed and expected numbers of suicides in the pandemic's first nine and first 10-15 months and used meta-regression to explore sources of variation.

    FINDINGS: We sourced data from 33 countries (24 high-income, six upper-middle-income, three lower-middle-income; 25 with whole-country data, 12 with data for area(s)-within-the-country, four with both). There was no evidence of greater-than-expected numbers of suicides in the majority of countries/areas-within-countries in any analysis; more commonly, there was evidence of lower-than-expected numbers. Certain sex, age and sex-by-age groups stood out as potentially concerning, but these were not consistent across countries/areas-within-countries. In the meta-regression, different patterns were not explained by countries' COVID-19 mortality rate, stringency of public health response, economic support level, or presence of a national suicide prevention strategy. Nor were they explained by countries' income level, although the meta-regression only included data from high-income and upper-middle-income countries, and there were suggestions from the ITS analyses that lower-middle-income countries fared less well.

    INTERPRETATION: Although there are some countries/areas-within-countries where overall suicide numbers and numbers for certain sex- and age-based groups are greater-than-expected, these countries/areas-within-countries are in the minority. Any upward movement in suicide numbers in any place or group is concerning, and we need to remain alert to and respond to changes as the pandemic and its mental health and economic consequences continue.

    FUNDING: None.

  19. Suggested Improvement in the Ing-Manske Procedure and Gabriel Synthesis of Primary Amines: Kinetic Study on Alkaline Hydrolysis of N-Phthaloylglycine and Acid Hydrolysis of N-(o-Carboxybenzoyl)glycine in Aqueous Organic Solvents
    Khan MN
    J Org Chem, 1996 Nov 15;61(23):8063-8068.
    PMID: 11667789
    A slight modification of the Gabriel synthesis of primary amines is suggested on the basis of the observed and reported values of rate constants for the alkaline and acid hydrolyses of phthalimide, phthalamic acid, benzamide, and their N-substituted derivatives. The suggested procedure requires shorter reactions time and milder acid-base reaction conditions compared with the conventional acid-base hydrolysis in the Gabriel synthesis. A slight modification in the Ing-Manske procedure is also suggested. Pseudo-first-order rate constants, k(obs), for hydrolysis of N-phthaloylglycine, NPG, decrease from 24.1 x 10(-3) to 7.72 x 10(-3) and 6.12 x 10(-3) s(-1) with increasing acetonitrile and 1,4-dioxan contents, respectively, from 2 to 50% v/v (all the percentages given in the paper are vol %), while increasing the organic cosolvents content from 50 to 80% increases k(obs) from 7.72 x 10(-3) to 19.7 x 10(-3) s(-1) for acetonitrile and from 6.12 x 10(-3) to 52.8 x 10(-3) s(-1) for 1,4-dioxan, in aqueous organic solvents containing 0.004 M NaOH at 35 degrees C. The rate constants for NPG hydrolysis decrease from 2.11 x 10(-2) to 1.19 x 10(-4) s(-1) with increasing MeOH content from 2 to 84%, in aqueous organic solvents containing 2% MeCN and 0.004 M NaOH at 35 degrees C.
  20. Study of environmental biodegradation of LDPE films in soil using optical and scanning electron microscopy
    Mumtaz T, Khan MR, Hassan MA
    Micron, 2010 Jul;41(5):430-8.
    PMID: 20207547 DOI: 10.1016/j.micron.2010.02.008
    An outdoor soil burial test was carried out to evaluate the degradation of commercially available LDPE carrier bags in natural soil for up to 2 years. Biodegradability of low density polyethylene films in soil was monitored using both optical and scanning electron microscopy (SEM). After 7-9 months of soil exposure, microbial colonization was evident on the film surface. Exposed LDPE samples exhibit progressive changes towards degradation after 17-22 months. SEM images reveal signs of degradation such as exfoliation and formation of cracks on film leading to disintegration. The possible degradation mode and consequences on the use and disposal of LDPE films is discussed.
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